Semiconductor element transfer method and semiconductor element transfer device

Abstract

Provided is a semiconductor element transfer method capable of protecting a semiconductor element from an impact applied to the semiconductor element when transferring the semiconductor element. Specifically, the semiconductor element transfer method includes a step for irradiating a transfer substrate Cr1 with laser light L from the side of the transfer substrate Cr1 opposite to the surface for adhesively holding a semiconductor element C, to thereby transfer the semiconductor element C to a transfer target substrate Cr2 while leaving an adhesive layer A1 on a surface of the semiconductor element C.

Description

Semiconductor element transfer method and semiconductor element transfer apparatus

[0001] The present invention relates to a semiconductor element transfer method and a semiconductor element transfer apparatus, and particularly relates to a semiconductor element transfer method and a semiconductor element transfer apparatus for transferring a semiconductor element adhesively held on a transfer substrate via an adhesive layer.

[0002] Conventionally, a semiconductor element transfer method for transferring a semiconductor element adhesively held on a transfer substrate via an adhesive layer is known (see, for example, Patent Document 1).

[0003] In the above-mentioned Patent Document 1, laser light is applied to a release layer (adhesive layer) from a side opposite to a side where elements (semiconductor elements) of a first substrate, on which the elements are provided via the release layer, are provided, thereby ablating (evaporating / vaporizing) the release layer to gasify the same, peeling the elements from the first substrate and transferring the elements to a second substrate. An element transfer method (transfer method) is disclosed. Further, in the above-mentioned Patent Document 1, the release layer is gasified so that no residue remains after irradiation with the laser light.

[0004] Japanese Unexamined Patent Publication No. 2010-251359

[0005] In the above-mentioned Patent Document 1, the release layer is completely ablated and gasified by irradiation with laser light so that no residue remains. Here, when transferring a fragile element (semiconductor element) such as a thin element, impact caused by ablation (evaporation / vaporization) of the release layer (adhesive layer) due to laser light irradiation is directly transmitted to the element, which may cause the element to crack. Therefore, there is a demand for a semiconductor element transfer method and a semiconductor element transfer apparatus capable of protecting a semiconductor element from impact applied to the semiconductor element during transfer of the semiconductor element.

[0006] The present invention has been made to solve the above problems, and one object of the present invention is to provide a semiconductor element transfer method and a semiconductor element transfer apparatus capable of protecting a semiconductor element from impact applied to the semiconductor element during transfer of the semiconductor element.

[0007] To achieve the above objective, the semiconductor element transfer method according to the first aspect of this invention comprises the steps of: holding a semiconductor element on a transfer substrate via an adhesive layer that is ablated by laser light irradiation by a laser light irradiation unit; and transferring a semiconductor element to a transfer substrate by irradiating the transfer substrate with laser light from the side of the transfer substrate opposite to the side of the transfer substrate that holds the semiconductor element, thereby not ablating the portion of the adhesive layer that is in contact with the semiconductor element and leaving the adhesive layer on the surface of the semiconductor element.

[0008] As described above, the semiconductor element transfer method according to this first phase includes a step of transferring the semiconductor element to the transfer substrate by irradiating the transfer substrate with laser light from the side opposite to the side of the transfer substrate that adhesively holds the semiconductor element, thereby transferring the semiconductor element to the transfer substrate while leaving the adhesive layer on the surface of the semiconductor element without ablation of the portion of the adhesive layer that is in contact with the semiconductor element. As a result, when transferring the semiconductor element, the portion of the adhesive layer that is in contact with the semiconductor element remains on the surface of the semiconductor element, and the surface of the semiconductor element is protected by the remaining adhesive layer. Therefore, when transferring the semiconductor element, the shock caused by the ablation (evaporation / vaporization) of the adhesive layer by the irradiation of laser light is not directly transmitted to the semiconductor element. As a result, the semiconductor element can be protected from shocks applied to it during the transfer of the semiconductor element. In addition, since the adhesive layer remains on the surface of the semiconductor element on the side irradiated with laser light, the laser light is not directly irradiated onto the semiconductor element during the transfer of the semiconductor element. As a result, the surface of the semiconductor element can be protected from laser light during the transfer of the semiconductor element.

[0009] In the semiconductor element transfer method according to the first aspect described above, preferably, the method further includes a step of dividing the adhesive layer between adjacent semiconductor elements so that each of the divided adhesive layers holds each of the multiple semiconductor elements. Here, when multiple semiconductor elements are held in adhesive layers that are not divided, the portion of the adhesive layer that holds the semiconductor elements and the portion that does not hold the semiconductor elements are connected. Therefore, in order to peel the semiconductor elements from the transfer substrate and transfer the semiconductor elements, it is necessary to divide the portion of the adhesive layer that holds the semiconductor elements and the portion that does not hold the semiconductor elements by irradiating it with laser light. Therefore, when multiple semiconductor elements are held in adhesive layers that are not divided, it is necessary to irradiate the adhesive layer with a relatively high-energy laser beam to divide the adhesive layer at the boundary between the portion that holds the semiconductor elements and the portion that does not hold the semiconductor elements. Therefore, if the method is configured to include a step of dividing the adhesive layer so that each of the divided adhesive layers holds each of the multiple semiconductor elements, the adhesive layer is already divided at the time of semiconductor element transfer, so it is not necessary to irradiate it with a high-energy laser beam to divide the adhesive layer, and the semiconductor elements can be peeled off from the transfer substrate. Therefore, the energy of the laser beam irradiated during transfer can be reduced.

[0010] In the semiconductor element transfer method according to the first aspect described above, preferably, the step of transferring the semiconductor element includes adjusting the amount of energy of the laser light irradiated onto the adhesive layer to be less than the amount of energy required to completely remove the adhesive layer, thereby transferring the semiconductor element while leaving the adhesive layer on the surface of the semiconductor element. With this configuration, since the amount of energy of the laser light irradiated onto the adhesive layer is less than the amount of energy required to completely remove the adhesive layer, the adhesive layer can be reliably left on the surface of the semiconductor element.

[0011] In the semiconductor element transfer method according to the first aspect described above, preferably, the method further includes a step of removing the adhesive layer remaining on the surface of the semiconductor element after the step of transferring the semiconductor element. Here, molten material (debris) scattered by ablation during semiconductor element transfer and etching residue remain on the surface of the semiconductor element, which can cause corrosion and changes in electrical conductivity. For this reason, after the semiconductor element transfer process and before bonding the semiconductor element to the mounting substrate, it is necessary to provide a cleaning step to remove molten material (debris) scattered by ablation during semiconductor element transfer, or etching residue. Therefore, if the method is configured to include a step of removing the adhesive layer remaining on the surface of the semiconductor element after the step of transferring the semiconductor element, the molten material (debris) scattered by ablation during semiconductor element transfer, or etching residue can be removed along with the adhesive layer remaining on the surface of the semiconductor element, thus eliminating the need for a separate cleaning step.

[0012] A semiconductor element transfer apparatus according to the second aspect of this invention comprises a laser light irradiation unit that irradiates a transfer substrate with laser light from the side opposite to the surface of the transfer substrate that holds the semiconductor element, on which the semiconductor element is held via an adhesive layer that is ablated by irradiation with laser light, and a control unit that performs control to transfer the semiconductor element while leaving the adhesive layer on the surface of the semiconductor element without ablating the portion of the adhesive layer that is in contact with the semiconductor element.

[0013] As described above, the semiconductor element transfer apparatus according to the second aspect of this invention is configured such that the control unit controls the transfer of the semiconductor element while leaving the adhesive layer on the surface of the semiconductor element without ablating the portion of the adhesive layer that is in contact with the semiconductor element. As a result, when the semiconductor element is transferred, the portion of the adhesive layer that is in contact with the semiconductor element remains on the surface of the semiconductor element, and the surface of the semiconductor element is protected by the adhesive layer. Therefore, when the semiconductor element is transferred, the shock caused by the ablation (evaporation / vaporization) of the adhesive layer by laser light irradiation is not directly transmitted to the semiconductor element. As a result, it is possible to provide a semiconductor element transfer apparatus that can protect the semiconductor element from shocks applied to the semiconductor element during transfer. Furthermore, since the adhesive layer remains on the surface of the semiconductor element on the side irradiated with laser light, the laser light is not directly irradiated onto the semiconductor element during transfer. As a result, it is possible to provide a semiconductor element transfer apparatus that can protect the surface of the semiconductor element from laser light during the transfer of the semiconductor element.

[0014] According to the present invention, as described above, it is possible to provide a semiconductor element transfer method and a semiconductor element transfer apparatus that can protect the semiconductor element from impacts applied to the semiconductor element during the transfer process.

[0015] This is a perspective view of a semiconductor element transfer apparatus according to one embodiment. This is a side view of a semiconductor element transfer apparatus according to one embodiment. This is a schematic diagram illustrating a semiconductor element on a transfer substrate according to one embodiment. This is a flowchart of a method for manufacturing a transfer substrate according to one embodiment. This is a schematic diagram illustrating a method for manufacturing a transfer substrate according to one embodiment. (a) This is a diagram illustrating the transfer of a semiconductor element. (b) This is a diagram illustrating the peeling off of the dicing tape. (c) This is a diagram showing the transfer substrate before etching. (d) This is a diagram showing the transfer substrate after etching. This is a flowchart of a method for transferring a semiconductor element according to one embodiment. This is a schematic diagram illustrating the transfer of a semiconductor element according to one embodiment. (a) This is a diagram illustrating the alignment of the transfer substrate and the substrate to be transferred. (b) This is a diagram illustrating the irradiation of laser light. (c) This is a diagram showing the state after the transfer of the semiconductor element has been completed. This is a schematic diagram illustrating the transfer of a semiconductor element by scanning with laser light. (a) This is a diagram illustrating the transfer of a semiconductor element held by a divided adhesive layer. (b) This is a diagram illustrating the transfer of a semiconductor element held by an undivided adhesive layer. This is a schematic diagram illustrating a modified example of a method for transferring a semiconductor element according to one embodiment. (a) This diagram illustrates the irradiation of a laser beam with a spot diameter larger than that of the semiconductor element. (b) This diagram illustrates the state in which the semiconductor element is transferred by the rupture of the adhesive layer.

[0016] Hereinafter, an embodiment of the present invention will be described based on the drawings.

[0017] (Configuration of Semiconductor Element Transfer Apparatus) Referring to Figures 1 to 8, the configuration of a semiconductor element transfer apparatus 100 according to one embodiment of the present invention will be described. As shown in Figure 1, the semiconductor element transfer apparatus 100 comprises a laser light irradiation unit 1, a transfer substrate holding stage 2, a substrate to be transferred holding stage 3, and a control unit 4. In the drawings, the left-right direction (one direction in the horizontal plane) of the semiconductor element transfer apparatus 100 is defined as the X direction. The right direction is defined as the X1 direction, and the left direction as the X2 direction. The up-down direction (vertical direction) of the semiconductor element transfer apparatus 100 is defined as the Z direction. The up direction is defined as the Z1 direction, and the down direction as the Z2 direction. The direction perpendicular to the X and Z directions (the other direction in the horizontal plane) of the semiconductor element transfer apparatus 100 is defined as the Y direction. One direction of the Y direction is defined as Y1, and the other direction as Y2.

[0018] As shown in Figures 1 and 2, the laser light irradiation unit 1 includes a laser light source 11, a galvanometer mirror 12, and an fθ lens 13. The laser light source 11 is a light source that emits laser light L and is configured to allow adjustment of the intensity of the laser light L. The wavelength of the laser light L is such that it causes ablation in the adhesive layer A1. The galvanometer mirror 12 is configured to be rotatable around two intersecting axes and reflects the laser light L at any angle. The fθ lens 13 focuses the laser light L from the galvanometer mirror 12 onto the adhesive layer A1 of the transfer substrate Cr1.

[0019] Furthermore, as shown in Figure 2, the transfer substrate holding stage 2 has a transfer substrate holding stage moving mechanism 21. This allows the transfer substrate holding stage 2 to move in the X, Y, and Z directions. The transfer substrate holding stage 2 is also configured to hold the transfer substrate Cr1. The transfer substrate holding stage 2 is also provided with an opening 2a. This allows the laser light irradiation unit 1 to irradiate the transfer substrate Cr1 held by the transfer substrate holding stage 2 with laser light L.

[0020] As shown in Figure 2, the transfer substrate Cr1 is provided with a plurality of adhesive layers A1 that are divided from each other. Adjacent semiconductor elements C are held on the transfer substrate Cr1 via the plurality of divided adhesive layers A1. Figure 3 shows that each of the divided adhesive layers A1 adhesively holds the semiconductor elements C. The semiconductor elements C are also adhesively held to the transfer substrate Cr1 via the adhesive layers A1 on the bonding surface Ca side. Here, when viewed from a direction perpendicular to the surface of the transfer substrate Cr1, the semiconductor elements C and the adhesive layers A1 that hold the semiconductor elements C are approximately the same shape and size. For example, the shape of the semiconductor elements C and the adhesive layers A1 are rectangular, and their size is 10 mm × 10 mm, respectively. The transfer substrate Cr1 is held on the transfer substrate holding stage 2 such that the semiconductor elements C held by the transfer substrate Cr1 via the adhesive layers A1 are positioned facing downwards (in the Z2 direction).

[0021] Furthermore, as shown in Figure 2, the substrate holding stage 3 has a substrate holding stage moving mechanism 31. This allows the substrate holding stage 3 to move in the X and Y directions. The substrate holding stage 3 also holds the substrate Cr2, which is the substrate to be transferred, for adhesively holding the semiconductor element C transferred from the transfer substrate Cr1.

[0022] Furthermore, as shown in Figure 2, the substrate Cr2 to be transferred is provided with an adhesive layer A2 for adhesively holding the transferred semiconductor element C. The substrate Cr2 is positioned such that the adhesive layer A2 side faces and is spaced apart from the adhesive layer A1 side of the transfer substrate Cr1.

[0023] The control unit 4 includes, for example, a CPU (Central Processing Unit), ROM (Read Only Memory), RAM (Random Access Memory), and GPU (Graphics Processing Unit) as processors, and is configured to control the laser light irradiation unit 1, the transfer substrate holding stage 2, and the transfer substrate holding stage 3.

[0024] (Method for Manufacturing Transfer Substrate) Referring to Figures 4 and 5(a) to 5(d), the process for manufacturing the transfer substrate Cr1 used in the semiconductor device transfer apparatus 100 according to one embodiment of the present invention will be described.

[0025] First, in step S1, as shown in Figure 4, the semiconductor element C is transferred onto the transfer substrate Cr1, which is provided with an adhesive layer A1. As shown in Figure 5(a), the individualized semiconductor element C is transferred onto the transfer substrate Cr1 while attached to the wafer ring Ri by dicing tape Dt. Here, the opposite side of the bonding surface Ca (the terminal portion of the semiconductor element C) is held in place by the dicing tape Dt so that it is held in place by the adhesive layer A1 when the semiconductor element C is mounted on the mounting substrate. After that, the process proceeds to step S2.

[0026] Next, in step S2, as shown in Figure 4, the adhesive layer A1 is brought into contact with the bonding surface Ca of the semiconductor element C. As a result, the semiconductor element C is held on the transfer substrate Cr1 via the adhesive layer A1 on the bonding surface Ca side when the semiconductor element C is mounted on the mounting substrate. After that, the process proceeds to step S3.

[0027] Next, in step S3, as shown in Figure 4, the dicing tape Dt is peeled off the semiconductor element C. Here, as shown in Figure 5(b), the dicing tape Dt is configured so that its adhesive strength weakens when exposed to ultraviolet light. Therefore, it is possible to easily peel the dicing tape Dt off the semiconductor element C after exposure to ultraviolet light. Figure 5(c) shows the state after the dicing tape Dt has been peeled off the semiconductor element C. After that, the process proceeds to step S4.

[0028] Next, in step S4 shown in Figure 4, the adhesive layer A1 is divided by etching. Specifically, as shown in Figure 5(c), the individual semiconductor elements C themselves are used as masks, and the adhesive layer A1 between multiple semiconductor elements C is removed by dry etching or wet etching. This removes the portion of the adhesive layer A1 that does not adhere to the semiconductor elements C. As a result, as shown in Figure 5(d), the adhesive layer A1 is divided such that, for adjacent semiconductor elements C, multiple semiconductor elements C are each held in the divided adhesive layer A1. Furthermore, since the semiconductor elements C themselves are used as masks, the size and shape of the adhesive layer A1 as viewed from a direction perpendicular to the surface of the transfer substrate Cr1 after etching are approximately the same as the size and shape of the semiconductor elements C. After this, the processing flow for the manufacturing method of the transfer substrate Cr1 is completed.

[0029] (Processing of Semiconductor Element Transfer Method) The processing of the semiconductor element transfer method according to one embodiment of the present invention will be described with reference to Figures 2, 6, 7(a) to (c), 8(a), and 8(b). The following description will be performed by the semiconductor element transfer apparatus 100 according to the semiconductor element transfer method flow shown in Figure 6.

[0030] In step S11, as shown in Figure 6, the control unit 4 (see Figure 2) adjusts the intensity of the laser beam L irradiated onto the adhesive layer A1 so that the amount of energy of the laser beam L is less than the amount of energy required to completely remove the adhesive layer. After that, the process proceeds to step S12.

[0031] Next, in step S12, as shown in Figure 6, the control unit 4 moves the transfer substrate holding stage 2 and the substrate to be transferred holding stage 3 to align the transfer substrate Cr1 and the substrate to be transferred Cr2. As a result, as shown in Figure 7(a), the position where the semiconductor element C on the substrate to be transferred Cr2 is transferred is positioned below (in the Z2 direction) the semiconductor element C that is adhesively held on the transfer substrate Cr1 via the adhesive layer A1. The distance d between the surface of the semiconductor element C and the surface of the adhesive layer A2 on the substrate to be transferred is set to a predetermined distance. For example, in this embodiment, if the chip size of the semiconductor element C is 10 mm × 10 mm and the chip thickness is 20 μm, the distance d is approximately 30 μm.

[0032] Next, in step S13, as shown in Figure 6, the semiconductor element C is transferred by irradiating it with laser light L. As shown in Figure 2, the laser light irradiation unit 1 irradiates the transfer substrate Cr1, on the side opposite to the side of the transfer substrate Cr1 that holds the semiconductor element C, via the adhesive layer A1 which is ablated by the irradiation of the laser light L, thereby transferring the semiconductor element C to the substrate Cr2.

[0033] Furthermore, in this embodiment, as shown in Figure 7(b), since the chip size of the semiconductor element C is larger than the spot size of the laser beam L, the semiconductor element C is transferred by scanning with the laser beam L.

[0034] In this embodiment, the size and shape of the adhesive layer A1, as viewed from a direction perpendicular to the surface of the transfer substrate Cr1, are approximately the same as the size and shape of the semiconductor element C. Therefore, as shown in Figure 8(a), a space S is created between the surface of the transfer substrate Cr1 and the adhesive layer A1 by ablation of the adhesive layer A1, making it possible to peel the semiconductor element C from the transfer substrate Cr1. On the other hand, as shown in Figure 8(b), if the adhesive layer A1 is not divided, the portion A1a that holds the semiconductor element C and the portion A1b that does not hold the semiconductor element C are connected by a boundary portion A1c. Therefore, when manufacturing the transfer substrate Cr1, if the adhesive layer A1 is not divided, it is necessary to break the boundary portion A1c during transfer, requiring control such as irradiating the boundary portion A1c with high-energy laser light L.

[0035] Next, in step S14, as shown in Figure 6, the control unit 4 determines whether the transfer of all semiconductor elements C is complete. If it is determined that the transfer of all semiconductor elements C is not complete, the process proceeds to step S12. If it is determined that the transfer of all semiconductor elements C is complete, the process flow for transferring semiconductor elements C is terminated. Here, as shown in Figure 7(c), at the point when the transfer of semiconductor elements C to the substrate Cr2 is complete, the portion of the adhesive layer A1 in contact with the semiconductor elements C remains on the surface of the semiconductor elements C without ablation. The remaining percentage of the adhesive layer A1 that remains on the surface of the semiconductor elements C without ablation is, for example, 1% to 99%. More preferably, the remaining percentage is, for example, 10% to 90%. In addition, molten material D (debris) scattered by ablation when transferring the semiconductor elements C, or etching residue R generated during etching, etc., are attached to the surface of the semiconductor elements C.

[0036] (Removal of the adhesive layer) Molten material D and etching residue R can cause corrosion of the semiconductor element C and reduce electrical conductivity when mounted on the substrate. Therefore, before bonding the semiconductor element C to the substrate, it is necessary to clean the semiconductor element C to remove the molten material D (debris) and etching residue R.

[0037] Furthermore, in this embodiment, since the adhesive layer A1 remains on the bonding surface Ca side of the semiconductor element C, it is also necessary to remove the adhesive layer A1 from the bonding surface Ca of the semiconductor element C when mounting the semiconductor element C onto the mounting substrate. For this reason, in this embodiment, in the cleaning process of the semiconductor element C after the transfer method, the molten material D (debris), etching residue R, and the adhesive layer A1 remaining on the surface of the semiconductor element are removed simultaneously. For example, wet cleaning using a chemical solution is performed.

[0038] (Effects of this embodiment) Next, the effects of this embodiment will be described.

[0039] In the semiconductor element transfer apparatus 100 of this embodiment, as described above, the transfer of the semiconductor element C to the transfer substrate Cr2 is controlled by irradiating the transfer substrate Cr1 with laser light L from the side opposite to the side of the transfer substrate Cr1 that adhesively holds the semiconductor element C. This prevents ablation of the portion of the adhesive layer A1 that is in contact with the semiconductor element C, leaving the adhesive layer A1 on the surface of the semiconductor element C. As a result, the portion of the adhesive layer A1 that is in contact with the semiconductor element C remains on the surface of the semiconductor element C when the semiconductor element C is transferred, thus protecting the surface of the semiconductor element C. Therefore, the shock when the adhesive layer A1 is ablated (evaporated / vaporized) by the irradiation of the laser light L is not directly transmitted to the semiconductor element C. As a result, the semiconductor element C can be protected from shocks applied to it during the transfer of the semiconductor element C. Furthermore, since the adhesive layer A1 remains on the surface of the semiconductor element C on the side irradiated with the laser light L, the laser light L is not directly irradiated onto the semiconductor element C during the transfer of the semiconductor element C. As a result, the surface of the semiconductor element C can be protected from the laser light L during the transfer of the semiconductor element C.

[0040] Furthermore, in this embodiment, as described above, the adhesive layer A1 provided on the transfer substrate Cr1 is divided between adjacent semiconductor elements C, so that each of the multiple semiconductor elements C is held in each of the divided adhesive layers A1 on the transfer substrate Cr1. Here, when multiple semiconductor elements C are held in adhesive layers A1 that are not divided, the portion A1a of the adhesive layer A1 that holds the semiconductor elements C and the portion A1b that does not hold the semiconductor elements C are connected by a boundary portion A1c. For this reason, in order to peel the semiconductor elements C from the transfer substrate Cr1 and transfer the semiconductor elements C, it is necessary to divide the portion A1a of the adhesive layer A1 that holds the semiconductor elements C and the portion A1b that does not hold the semiconductor elements C by irradiation with laser light L. Accordingly, when multiple semiconductor elements are held in adhesive layers A1 that are not divided, it is necessary to irradiate the adhesive layer A1 with a relatively high-energy laser light L in order to divide the adhesive layer A1 at the boundary portion A1c between the portion A1a that holds the semiconductor elements and the portion A1b that does not hold the semiconductor elements. Therefore, if the adhesive layer A1 of the transfer substrate Cr1 is configured to be divided such that each of the multiple semiconductor elements C is held in each of the divided adhesive layers A1, then at the time of transfer of the semiconductor elements C, the adhesive layer A1 is already divided, eliminating the need to irradiate the adhesive layer A1 with high-energy laser light L to divide it, and the semiconductor elements C can be peeled off from the transfer substrate Cr1. As a result, the energy of the laser light L irradiated during transfer can be reduced.

[0041] Furthermore, in this embodiment, as described above, the control unit 4 is configured to adjust the energy amount of the laser light L irradiated from the laser light source 11 so that the energy amount of the laser light L irradiated onto the adhesive layer A1 is less than the energy amount required to completely remove the adhesive layer A1. As a result, since the energy amount of the laser light L irradiated onto the adhesive layer A1 is less than the energy amount required to completely remove the adhesive layer A1, the adhesive layer A1 can be reliably left on the surface of the semiconductor element C.

[0042] Furthermore, in the present embodiment, as described above, the adhesive layer A1 remaining on the surface of the semiconductor element C after the semiconductor element C is transferred to the transfer target substrate Cr2 is removed. Here, corrosion and changes in electrical conductivity occur due to molten material D (debris) scattered by ablation during transfer of the semiconductor element C and etching residue R remaining on the surface of the semiconductor element C. For this reason, after the transfer step of the semiconductor element C and before bonding the semiconductor element C to the mounting substrate, it is necessary to provide a cleaning step for removing the molten material D (debris) scattered by ablation during transfer of the semiconductor element C, the etching residue R, or the like. Therefore, by removing the adhesive layer A1 remaining on the surface of the semiconductor element C after transferring the semiconductor element C onto the transfer target substrate Cr2, the molten material D (debris) scattered by ablation during transfer of the semiconductor element C or the etching residue R can be removed together with the adhesive layer A1 remaining on the surface of the semiconductor element C, which eliminates the need to provide a separate cleaning step.

[0043] [Modification] It should be understood that the embodiment disclosed herein is illustrative in all respects and not restrictive. The scope of the present invention is defined by the claims rather than the above description of the embodiment, and includes all modifications (modifications) within the meaning and scope equivalent to the claims.

[0044] For example, in the above embodiment, an example is shown in which a portion of the adhesive layer A1 where the semiconductor element C is not adhesively held is removed by etching, but the present invention is not limited thereto. As long as each of the plurality of semiconductor elements C is held by each of the mutually divided adhesive layers A1, portions where no semiconductor elements C are adhesively held may remain.

[0045] Furthermore, in the above embodiment, an example is shown in which etching is performed using the semiconductor element C itself as a mask, but the present invention is not limited thereto. A separate mask for etching the adhesive layer A1 may be prepared.

[0046] Furthermore, in the above embodiment, an example is shown in which the plurality of semiconductor elements C are each held by the mutually divided adhesive layers A1, but the present invention is not limited thereto. It is only required that the semiconductor element C can be transferred to the transfer-receiving substrate Cr2 while the adhesive layer A1 remains on the surface of the semiconductor element C. Specifically, as shown in FIG. 9(a), the laser beam L having a spot diameter larger than that of the semiconductor element C may be irradiated. In this case, as shown in FIG. 9(b), by irradiating the laser beam L until the boundary portion A1c is fractured due to the self-weight of the semiconductor element C, the impact during ablation or the like, the semiconductor element C may be transferred to the transfer-receiving substrate Cr2 while the adhesive layer A1 remains on the surface of the semiconductor element C.

[0047] Furthermore, in the above embodiment, an example is shown in which the energy amount of the laser beam L irradiated to the adhesive layer A1 is adjusted by adjusting the intensity of the laser beam L emitted from the laser light source 11, but the present invention is not limited thereto. The irradiation time of the laser beam L may be changed, or when a pulse laser is used, the pulse width may be changed.

[0048] Furthermore, in the above embodiment, an example is shown in which the semiconductor element C is adhesively held on the transfer substrate Cr1 by the adhesive layer A1 on the bonding surface Ca side of the semiconductor element C to the mounting substrate, but the present invention is not limited thereto. The semiconductor element C may be adhesively held on the transfer substrate Cr1 by the adhesive layer A1 on the opposite side of the bonding surface Ca.

[0049] 1 Laser beam irradiation unit 2 Transfer substrate holding stage 2a Opening 3 Transfer-receiving substrate holding stage 4 Control unit 11 Laser light source 12 fθ lens 21 Transfer substrate holding stage moving mechanism 31 Transfer-receiving substrate holding stage moving mechanism 100 Semiconductor element transfer device A1 Adhesive layer A2 Transfer-receiving substrate adhesive layer C Semiconductor element Cr1 Transfer substrate Cr2 Transfer-receiving substrate Dt Dicing tape L Laser beam

Claims

1. A semiconductor element transfer method comprising:

1. The step of adhesively holding a semiconductor element on a transfer substrate via an adhesive layer that is ablated by irradiation with laser light from a laser light irradiation unit; and 2. The step of irradiating the transfer substrate with the laser light from the side of the transfer substrate opposite to the side of the transfer substrate that adhesively holds the semiconductor element, thereby transferring the semiconductor element to the transfer substrate while leaving the adhesive layer on the surface of the semiconductor element without ablating the portion of the adhesive layer that is in contact with the semiconductor element.

2. The semiconductor transfer method according to claim 1, further comprising the step of dividing the adhesive layer between adjacent semiconductor elements so that each of the plurality of semiconductor elements is held in each of the divided adhesive layers.

3. The semiconductor element transfer method according to claim 1, wherein the step of transferring the semiconductor element includes adjusting the amount of energy of the laser light irradiated onto the adhesive layer to be less than the amount of energy required to completely remove the adhesive layer, thereby transferring the semiconductor element while leaving the adhesive layer on the surface of the semiconductor element.

4. The semiconductor element transfer method according to claim 1, further comprising the step of removing the adhesive layer remaining on the surface of the semiconductor element after the step of transferring the semiconductor element.

5. A semiconductor element transfer apparatus comprising: a laser beam irradiation unit that irradiates a focused laser beam toward the transfer substrate, wherein the transfer substrate on which the semiconductor element is held is positioned on the opposite side of the surface holding the semiconductor element; and a control unit that controls the transfer of the semiconductor element by irradiating the transfer substrate with the laser beam from the opposite side of the transfer substrate to which the semiconductor element is held adhesively, thereby preventing ablation of the portion of the adhesive layer that is in contact with the semiconductor element and leaving the adhesive layer on the surface of the semiconductor element.

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